Conventionally, communication medium protocol stacks have been single entities with top-level control interfaces and dedicated hardware resources. This means that a protocol stack presents a single entity and identity of the device, respectively, on the communication medium towards one or more other counterpart devices, with which the device is enabled to communicate using the communication medium.
In particular, the radio access protocol stack of wireless devices is typically implemented to present the wireless device as a single entity in a single physical network thereby acting in a single role at a point in time. This means that such wireless devices may either act as master or slave devices at a point in time from the network perspective. Switching between the role as master and slave, respectively, requires cancelling of the one or more currently established communication connections, reconfiguration of the role of the device and establishing new communication connection(s), which necessarily implies losing all ties to the former (network related) state of the device in the network. The device is not able to restore its former (network related) state in the network such as role, identity etc. without re-executing the network joining procedure.
Prior art WO 2009/083912 A2 published on Jul. 9, 2009 describes a controller, which is configured to instantiate a plurality of radio protocols and to operate the plurality of radio protocols with a physical layer. Each instantiation of a same radio protocol is embodied in a same code module and with associated data stored in a memory. The controller is further configured to execute each instantiation of a radio protocol so that a portion of resources are shared between different instantiations of radio protocols, and different instantiations of the radio protocols do not interfere with each other.
Prior art WO 2007/097941 A1 published on Aug. 30, 2007 describes a wireless network device, which includes a first media access controller (MAC) and a second media access controller (MAC). The first media access controller and the second media access controller are connected to a same baseband processor in communication with a radio frequency transmitter, which selectively transmits one of the signals outputted by the first and second media access controllers (MACs). An arbitration logic is suggested, which determines priority between the first and second media access controllers (MACs) according to a predetermined hierarchy and instructs selective switching of the output signals. A signal indicates to the media access controllers (MACs) whether communication is available or unavailable.
Prior art WO 2005/002257 A1 published on Jan. 6, 2005 describes a single radio apparatus, which supports multiple wireless communication standards in that communications with the multiple communication standards are operated by time interleaving of the communications. The single radio device of WO 2005/002257 A1 is configured to order the supported communication standards in a hierarchy to provide priority to certain communications. Time interleaving wireless communications over standards that support burst communications, such as time multiplexed wireless communication systems or wireless packet data systems, allow a single radio to seamlessly support multiple standards without loss of data.
However, the scheduling and/or arbitration methodologies suggested in the prior art do not meet the requirement of flexibility. In prior art, switching between roles and networks requires a full reconfiguration, which implies losing all ties to the past role and network, i.e. the device cannot restore its original state in the network without re-executing the network joining procedure